Although it can be used in various applications for filling joint transitions or grooves of a wide range of structures, the present disclosure and the problem that it addresses are described in greater detail in relation to the application of a filling compound in the field of airplane wings. In principle, however, the present disclosure is also usable for filling joint transitions, joint grooves or grooves in general vehicles, such as road vehicles, railway vehicles and/or water vehicles or the like.
Designing efficient aircraft which have as low a fuel consumption and associated pollutant emission as possible is a key challenge in modern aircraft construction. For this purpose, there is intensive research as to how improved wings can contribute to environmentally friendlier air traffic. Thus, in particular the level of flow drag of an airplane is rather crucially influenced by the specific, speed-dependent flow progression of the air over the surfaces of the airplane airfoils. The more uniformly this flow progresses, the lower the drag. A low drag in turn reduces the fuel consumption, the emission of pollutants and thus also the energy costs. One pursued approach thus involves optimising wing constructions to the effect that a uniform, in other words laminar, flow can be maintained in the long term without the occurrence of turbulences, which would lead to an increased drag again.
For this purpose, it is advantageous to design the surfaces of the airfoils and in particular the wing faces oriented in the direction of flight so as to be as smooth as possible. Even very slight bumps on the surfaces due to dirt, mounting imprecisions and/or painting imprecisions can influence a laminar flow on the wing. Approaches for laminar wings have a rigid leading wing edge which is rigidly connected to a wing box. When a leading wing edge of this type is connected to the wing box, this results in a joint transition which should be filled as evenly as possible with a filling compound so as to meet applicable requirements for maintaining a laminar flow.
Typically, joint transitions or joint grooves are manually filled with filling compound and subsequently manually smoothed. For this purpose, application of the filling compound may be preceded by masking the faces adjacent to the joint groove so as to protect these faces from being soiled by the filling compound. Precise application of the masking is typically time-consuming, but can at the same time be decisive as to the quality of the subsequent filling. Generally, it is found to be difficult to meet the strict requirements for the filling compound surface of a laminar wing by a manual filling process. In particular, in order to provide the required tolerances, it may sometimes be necessary to repeat the filling and smoothing process on a number of occasions in succession.